The new 33XC & 37XC cartridges designed by David Tubb

Care to tell everyone where the 33XC and 37XC came from prior to Tubb designing it?
Care to tell everyone where the 33XC and 37XC came from prior to Tubb designing it?
told my self that I would not go there. ill let someone else tell that story. The point of my comment was to inform that it was good and why the lapua long cylinder was used by Mr. Tubb
 
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Not at all true. the 375 cheytac is not overbore. Case fill % is higher then that of the xc in 338. The 375 cheytac runs very low S.d.s with quality load development its around 4 fps. The Xc cartridge is a good design tried and proven Prior to Tubb... and was a great choice to the use of his Tubb Gun design sence it wont take a cheytac round. the 375 xc is underbore and could use more capacity .

Likewise...."not all true". He used rebated Cheytac case before coming out with XC case--so he can run a Cheytac case in his rifle. First he went with improved Lapua, then Peterson made him a rebated Cheytac case. Finally he developed the XC case.
I was told with the 375 Cheytac--due to early signs of firecracking / dry lake effect that he was seeing in his bore scope and the difficulty in achieving stable nodes for various reasons, is what made him venture to develop the XC case. So please educate me if this is not true. If I was simply marketed to as a selling point, then please tell us. What are the fill ratios, and with what powders, are you achieving with 375 Cheytac in single digit SD's? What is the extent of the nodes you are achieving? What's your variance of grains of powder yet that are still single digit? What MV's are you getting, with what grain bullets, and at what COAL? When are you seeing throat erosion, at what round count? What is your total round count for 375 Cheytac when it burns out? Also would like to know.... "The Xc cartridge is a good design tried and proven Prior to Tubb"...so who designed it? You've got my curiosity, I'm all ears.
 
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Hi,

LOLOL
anyone-hungry-this-could-be-a-while-popcorn-meme.jpg


Sincerely,
Theis

PS: If anyone is questioning badass due to his new account and/or low post count...I would suggest otherwise.
 
Good to know... Not another troll on this site. But seriously, I'm here to learn. That's why I love this site.
Like I said , I told my self I would not go there. But I will make some comments and will not point fingers in any direction. Nor try to call any one out. Squibbler you seem to know a fair amount about the story of the life and times of the xc development. Not sure if it was a story you read some where or it was personal and or first hand . ill try to make this short. the cheytac case due to volume will have a shorter throat life thus causing fire cracking. and yes the h20 of the lapua long cylinder being less and using less will help with round count . but sd/s are directly related to load development inc cartridge prep and case design. powder, bullets , barrels and pressure nodes will all effect sd end results simply put the cheytac case would not be used if it was not possible to get low #,s As for using a rebated cheytac case in a tenon designed for a lapua case it would be real hard to run pressures needed to see the low sd,s that are in most cases at the upper end of load development node with out seeing some sort of issues . like bolt lift or extraction issues from tenon flex . Moving away from the cheytac case in rebated form was a wise move on his part considering there are issues with undercut diameter in relation to I.D. of the cartridge. simply put it will never realize optimized outcome in performance . now the use of the lapua long cylinder is not new its been being used by Kirby in his raptor cases in both 300 and 338 for many years now. as well as the development and use in the 358 jager 8mm Bullwinkle and the 375 wildcat ( cartridge name is wildcat ) So while the 338 and 375 xc was design by him its not new its just another variation a shermanized virsion as per say . it was a good choice for his application at least I thought so long before he even did it.
 
Like I said , I told my self I would not go there. But I will make some comments and will not point fingers in any direction. Nor try to call any one out. Squibbler you seem to know a fair amount about the story of the life and times of the xc development. Not sure if it was a story you read some where or it was personal and or first hand . ill try to make this short. the cheytac case due to volume will have a shorter throat life thus causing fire cracking. and yes the h20 of the lapua long cylinder being less and using less will help with round count . but sd/s are directly related to load development inc cartridge prep and case design. powder, bullets , barrels and pressure nodes will all effect sd end results simply put the cheytac case would not be used if it was not possible to get low #,s As for using a rebated cheytac case in a tenon designed for a lapua case it would be real hard to run pressures needed to see the low sd,s that are in most cases at the upper end of load development node with out seeing some sort of issues . like bolt lift or extraction issues from tenon flex . Moving away from the cheytac case in rebated form was a wise move on his part considering there are issues with undercut diameter in relation to I.D. of the cartridge. simply put it will never realize optimized outcome in performance . now the use of the lapua long cylinder is not new its been being used by Kirby in his raptor cases in both 300 and 338 for many years now. as well as the development and use in the 358 jager 8mm Bullwinkle and the 375 wildcat ( cartridge name is wildcat ) So while the 338 and 375 xc was design by him its not new its just another variation a shermanized virsion as per say . it was a good choice for his application at least I thought so long before he even did it.


Thanks for the input. It appears to me that your in the... "no replacement for displacement camp." So let me ask you this question...In your opinion, based off your experience, what's the 6.5 Creedmoor of ELR cartridges? i.e.--what's the sweet spot? And I state this as a non-rhetorical question, would appreciate your honest opinion.

@THEIS .... Thank you for reference
 
Thanks for the input. It appears to me that your in the... "no replacement for displacement camp." So let me ask you this question...In your opinion, based off your experience, what's the 6.5 Creedmoor of ELR cartridges? i.e.--what's the sweet spot? And I state this as a non-rhetorical question, would appreciate your honest opinion.

@THEIS .... Thank you for reference
well that's a good question . the term ELR is a funny word or phrase it means different things to different people . but for the sport has been recognized by the majority as starting at 1500 yards and goes to 3500 plus so considering that I am 100 % for what ever advances the sport as far as possible I will never shoot a 338 of any kind I don't think its advancing the sport , not to be confused with currently competitive at the distances that most elr matches end at. ( trust me it wont stay that way ) some would think its the 375 cheytac well its maxed out for the most part and has serves well but still limiting the sport , the strange part is every one has ignored the 408 cheytac and very little focus has been spent on developing the 408 bullet I think it could be perhaps developed to be the best all around elr caliber for the next 2 to 5 years but would need to be optomozed in about 195 grain case. that's not the barret / bmg case too many issues I may regret this comment just like other I have made but a cheytac cylinder long case ( like what david tubb used in the lapua case for his 375 xc ) necked and improved to 408 would be the new super star of elr the 416 barrett and 460 will be short lived and is too expensive for the average joe . I am in the no replacement in the performance base displacement group but would never choose displacement over accuracy supported by low sd,s
 
well that's a good question . the term ELR is a funny word or phrase it means different things to different people . but for the sport has been recognized by the majority as starting at 1500 yards and goes to 3500 plus so considering that I am 100 % for what ever advances the sport as far as possible I will never shoot a 338 of any kind I don't think its advancing the sport , not to be confused with currently competitive at the distances that most elr matches end at. ( trust me it wont stay that way ) some would think its the 375 cheytac well its maxed out for the most part and has serves well but still limiting the sport , the strange part is every one has ignored the 408 cheytac and very little focus has been spent on developing the 408 bullet I think it could be perhaps developed to be the best all around elr caliber for the next 2 to 5 years but would need to be optomozed in about 195 grain case. that's not the barret / bmg case too many issues I may regret this comment just like other I have made but a cheytac cylinder long case ( like what david tubb used in the lapua case for his 375 xc ) necked and improved to 408 would be the new super star of elr the 416 barrett and 460 will be short lived and is too expensive for the average joe . I am in the no replacement in the performance base displacement group but would never choose displacement over accuracy supported by low sd,s Size does not matter if its lame or limp
 
Guys, when I had a 375 Cheytac, or I should say we, because my friend and I both had Lawton builds, we were plagued with hangfires, not every time but one in a short while.

Yes we used Fed 215M primers and tried nearly every powder available at the time.

Also I have read throughout the years of others having the same ignition problems.

Isn't it going the wrong way using bigger cases with ever increasing powder capacity and staying with a primer not designed to work with the huge amounts of powder I'm seeing mentioned in this thread?????
 
Guys, when I had a 375 Cheytac, or I should say we, because my friend and I both had Lawton builds, we were plagued with hangfires, not every time but one in a short while.

Yes we used Fed 215M primers and tried nearly every powder available at the time.

Also I have read throughout the years of others having the same ignition problems.

Isn't it going the wrong way using bigger cases with ever increasing powder capacity and staying with a primer not designed to work with the huge amounts of powder I'm seeing mentioned in this thread?????

What was your case fill like with the 375ct? I have never owned one but I’m guessing case fill was less than optimal??
 
What was your case fill like with the 375ct? I have never owned one but I’m guessing case fill was less than optimal??

Going off memory here but I think our charge that we settled on was 132 grains of Retumbo. Heavy charges of H869 and H870 lessened the hangfires but those are very temp sensitive powders and dirty burning. Just guessing on fill percentage with Retumbo at 85-90%??? I think it was about a 8th of an inch below the shoulder.

In hindsight I personally would have been happier with a 338 Lapua AI and lived with the smaller dust signature at distance.
 
Take the CCI 450 SRP for instance. At what point would one stop when it concerns powder capacity and when would we expect it to not ignite a charge optimally.

It works okay with 6x47l, 6mmCreed, 308SRP brass, but how about 284, or 30-06, etc, if brass were offered with SRP in those bigger cases. It gets to the point of not going there.
 
I will never shoot a 338 of any kind I don't think its advancing the sport , not to be confused with currently competitive at the distances that most elr matches end at. ( trust me it wont stay that way )

There might also be a difference however between practical man carried, field portable ELR for what a single person can easily carry a fair distance and shoot by themselves and hit without a team of spotters and people calculating the numbers for them, and be of practical use for targeting 4 legged or 2 legged critters.

And the other path which seems to be effectively headed towards half inch (+/- minus a bit) caliber direct aimed field artillery pieces that are vehicle carried only and "crew served" at dedicated ranges against huge static targets.
 
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There might also be a difference however between practical man carried, field portable ELR for what a single person can easily carry a fair distance and shoot by themselves and hit without a team of spotters and people calculating the numbers for them, and be of practical use for targeting 4 legged or 2 legged critters.

And the other path which seems to be effectively headed towards half inch (+/- minus a bit) caliber direct aimed field artillery pieces that are vehicle carried only and "crew served" at dedicated ranges against huge static targets.
agreed but elr is not marketing or sales of a package or product . its about extending or pushing the limits further and further. sales is a results of the outcome. it clearly obvious that some have used elr for marketing a product but when that product is not or is no longer competitive the idea or bill of goods slowly fades away. people are like sheep what wins sales look at benchrest f class been that way for 40 plus years now. Every one seems to be following the elr builds based on chassis and short barrels. the TacCool look I don't see it as true elr I see it as over flow from some sort of PRS ELR
 
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I spoke with Tyler at Tubbs operation and I was told that my sizing and seating dies are in the mail. I'm hoping the package will arrive tomorrow (1/4/2019) but UPS thinks it is more likely it shows up on Monday (1/7/2019). I'll let everyone know if both dies are in there.
 
Ran a 500 yd. ladder on the 33xc today with 300 Berger OTM’s an h50bmg. The 277 mtac’s I tried just seemed erratic at 2010yds on two different occasions. Ran the ladder today and then hurried back to the shop before the sun went down and loaded up 6 rounds of 122.7 Took a couple rounds to get dope and ended up with two hits on steel as the sun was going down. The Berger’s seem way more consistent than the mtac’s at 2010yds. When I get more time I’ll mess with this load and seating depth if needed as it looks to have good potential.

Anxiously waiting to try the new 285 Warner !!!
 
Ran a 500 yd. ladder on the 33xc today with 300 Berger OTM’s an h50bmg. The 277 mtac’s I tried just seemed erratic at 2010yds on two different occasions. Ran the ladder today and then hurried back to the shop before the sun went down and loaded up 6 rounds of 122.7 Took a couple rounds to get dope and ended up with two hits on steel as the sun was going down. The Berger’s seem way more consistent than the mtac’s at 2010yds. When I get more time I’ll mess with this load and seating depth if needed as it looks to have good potential.

Anxiously waiting to try the new 285 Warner !!!
what twist are you running?
 
well that's a good question . the term ELR is a funny word or phrase it means different things to different people . but for the sport has been recognized by the majority as starting at 1500 yards and goes to 3500 plus so considering that I am 100 % for what ever advances the sport as far as possible I will never shoot a 338 of any kind I don't think its advancing the sport , not to be confused with currently competitive at the distances that most elr matches end at. ( trust me it wont stay that way ) some would think its the 375 cheytac well its maxed out for the most part and has serves well but still limiting the sport , the strange part is every one has ignored the 408 cheytac and very little focus has been spent on developing the 408 bullet I think it could be perhaps developed to be the best all around elr caliber for the next 2 to 5 years but would need to be optomozed in about 195 grain case. that's not the barret / bmg case too many issues I may regret this comment just like other I have made but a cheytac cylinder long case ( like what david tubb used in the lapua case for his 375 xc ) necked and improved to 408 would be the new super star of elr the 416 barrett and 460 will be short lived and is too expensive for the average joe . I am in the no replacement in the performance base displacement group but would never choose displacement over accuracy supported by low sd,s

Badass wrote " I have made but a cheytac cylinder long case ( like what david tubb used in the lapua case for his 375 xc ) necked and improved to 408 would be the new super star of elr the 416 barrett and 460 will be short lived and is too expensive for the average joe" .


Whether or not your new 408 is the next ELR superstar is yet to be determined. You are welcome to come to GA and show us as I am very interested in seeing its performance. I have access to a private range with steel out to 2500 yards. There is always Blakely as they have steel out to about 2300. The invitation is always open.

Yes, the 416 and 460 Steyr are specialized cartridges and anyone wanting to play the game, at the top level, is not the "average joe". Just like drag racing, money is NO object when it comes to winning. At the top $8-10,000 rifles, $3 bullets, $5-7 cases, etc. are the norm, not the exception.

From a sheer performance stand point I have a hard time envisioning how a 408 whatever is gong to better the 460 Steyr or a full length 458/50. I have shot just about every elr combination out there, in some form or another, however, in this case, I could be wrong.

Lastly, please expatiate on the "issues" with the 416 or 50BMG case.

Precision first then accuracy.
YMMV.

EJ
 
Yes, cost is a big factor for using a 50BMG case. But you can't deny the added BC advantage that the larger 416 and 458 bullets will give.

One of the other issues are the pressure limits of the current brass available. JeffVN mentioned that some of this can be resolved by work hardening the brass first with reduced loads... Ideally we need a manufacturer to come out with a stronger case.

The final issue, at this time, seems to be finding slow burning powders that are not so temp sensitive and have good case fill for those big overbore cases. I believe Dan and Al Warner are working on future powder options that might work.
 
Badass wrote " I have made but a cheytac cylinder long case ( like what david tubb used in the lapua case for his 375 xc ) necked and improved to 408 would be the new super star of elr the 416 barrett and 460 will be short lived and is too expensive for the average joe" .


Whether or not your new 408 is the next ELR superstar is yet to be determined. You are welcome to come to GA and show us as I am very interested in seeing its performance. I have access to a private range with steel out to 2500 yards. There is always Blakely as they have steel out to about 2300. The invitation is always open.

Yes, the 416 and 460 Steyr are specialized cartridges and anyone wanting to play the game, at the top level, is not the "average joe". Just like drag racing, money is NO object when it comes to winning. At the top $8-10,000 rifles, $3 bullets, $5-7 cases, etc. are the norm, not the exception.

From a sheer performance stand point I have a hard time envisioning how a 408 whatever is gong to better the 460 Steyr or a full length 458/50. I have shot just about every elr combination out there, in some form or another, however, in this case, I could be wrong.

Lastly, please expatiate on the "issues" with the 416 or 50BMG case.

Precision first then accuracy.
YMMV.

EJ
first of all is was giving a example of what could be done using a a 408 bullet in a long cylinder chaytac case a long cylinder like what david tudd did and Kirby allen did in the raptor. I have no plans on using a long cheytac cylinder and don't have one built. we have made stuff much larger that that. my point still stands you could end up with a easy 195 grain h20 case that could be run at high pressures with a high bc 408 bullet and match or surpass the velocities run in the barrett case considering the barrett has pressure limits way below that of a cheytac case. and is prone to hard extraction and bolt lift issues and bolt thrust issues . now the bullet is no different then any other bullet diameter maxed out has roughly X B.C. dictated by diameter and stabilized length, weight and design. a optimized 408 could have a higher bc the currently made 416 bullets it just need to be exploited the same way all the other elr calibers have been. As far as showing up to shoot at GA no thanks I do that here at much further distances. thanks for the offer though. perhaps ill see you at future elr matches using my 420 blitzkrieg . ps I said I may regret the comment like other comments I have made but..... I did not say I have made a 408 long cylinder cartridge
 
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What velocity were you seeing with the 300 bergers? With a throat cut to run 300 bergers, will the flatlines still reach the lands in your chamber?


My chamber is actually cut for solids. The 300 OTM’s ended up seated a bit deeper than I wanted but not by much. I started out with 277 mtac’s but just wasn’t getting the accuracy I wanted at 2k so I tried the 300 OTM’s. I didn’t push them real hard because of the fast twist but I ran a quick ladder at 500 yds with them and found a good node. Sent about 7-8 at 2000 yds and accuracy looked significantly better than the mtac’s. I have some 285 flatlines now that I’m going to try. Those were my intended bullet all along just took longer to get them than I first planned.

300 OTM ladder with h50bmg. I never reach pressure with this ladder.
 

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My chamber is actually cut for solids. The 300 OTM’s ended up seated a bit deeper than I wanted but not by much. I started out with 277 mtac’s but just wasn’t getting the accuracy I wanted at 2k so I tried the 300 OTM’s. I didn’t push them real hard because of the fast twist but I ran a quick ladder at 500 yds with them and found a good node. Sent about 7-8 at 2000 yds and accuracy looked significantly better than the mtac’s. I have some 285 flatlines now that I’m going to try. Those were my intended bullet all along just took longer to get them than I first planned.

300 OTM ladder with h50bmg. I never reach pressure with this ladder.

Bravo,
Have to tried any other powders like RL33 ,RL26 and VHT570?
 
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I ordered sizing and seating dies along with some brass on monday last week and they were here wed. Still trying to figure out what barrel blank to use and twist rate. Looking at using solids and probably 30-32" barrel in the Desert Tactical. The reamer and guages have been here a while.....

Frank
 
Rl33 not temp stable..... Would you elaborate on this

Hi,
It is pretty commonly known that RL propellants fluctuate MVs due to changing ambient temperatures.
It is common for RL33 to fluctuate IIRC around 1.5fps per 2 degree ambient temperature changes.

Sincerely,
Theis

Here is quote from Alliant Technical Services (Copied from another forum)...

Alliant has three temp stable propellants by their chemistry. These are AR-Comp, Reloder-16 and Reloder-23.* Reloder-26 by its chemistry is not temp stable, but in most applications it behaves much like a temp stable propellant.* The Reloder-33 is not at temp stable propellant. That being said, all of our propellants need to pass, by lot, testing procedures in a wide range of temperatures, wider than any self-respecting human would be hunting or shooting under.
As for load data for the 28 Nosler, Alliant has no tested load data for this cartridge at this time.
I will submit your request to the engineering lab for possible future development. But, there is no timetable as to when this may be looked at for development.
Thanks,
Duane V.
Technical Services Rep
Alliant/Blazer/CCI/Speer
 
375CT or 37XC for my ELR build?
I heard the 37XC can be loaded on a Dillion 650 press which id like. Can’t find any information if the 375CT can be loaded on a 650.

I’m thinking about having JJRock build me a complete rifle. They’re right down the road from me which seems nice.

Thanks
 
I'm just now getting comfortable with 375CT, seems like 5 years ago we were all scrounging for Jamison brass and swearing at the awful Bertnam and wondering which dimensions our reamers were (like comparing Kiff's to Cheytac's dims). What a difference a few years makes with the explosion of ELR into the mainstream.

As long as Peterson is involved, it feels more legit and doable. David and his business is probably much better to deal with than the whole Cheytac drama. I'd consider moving away from 375CT when my Bartlein is shot out. I am not seeing fire cracking yet though.

I just hate it when one cartridge gets some traction and another one comes along.
 
in the 375 your better off with the CT for performance . in 338 the xc shines. The cheytac and xc are
same length roughly but the xc can use 7/8 " dies where the cheytac needs 1.250 12 tpi dies. disogodfather kiffs revision d chaytac reamers are the same as the latest cheytac usa chambers considering he is the one who made them for them get the Peterson brass and you should not have any problems all other brass for the cheytac is inferior
 
in the 375 your better off with the CT for performance . in 338 the xc shines. The cheytac and xc are
same length roughly but the xc can use 7/8 " dies where the cheytac needs 1.250 12 tpi dies. disogodfather kiffs revision d chaytac reamers are the same as the latest cheytac usa chambers considering he is the one who made them for them get the Peterson brass and you should not have any problems all other brass for the cheytac is inferior

Yeah I have been shooting the Peterson since it came out, total game changer. When did Dave revise his reamers? Mine is from 2015.
 
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I am thinking about running the 33XC in a Surgeon XL single shot action. That action has a 3.350" ejection/loading port length. Will the 4.5"+ 33XC cartridges easily feed and eject from a standard (Lapua) length port?

Is there any other reason to be concerned about using the Surgeon XL with the XC cartridges?
 
One other question - is the 33XC loaded with 285/300 grain bullets worth it considering the lack of availability of H50BMG? Are people having good luck/good case fill with RL33?

I've heard 570 thrown around as a viable option, but it may as well not exist as far as I'm concerned. I've never seen it available anywhere.
 
One other question - is the 33XC loaded with 285/300 grain bullets worth it considering the lack of availability of H50BMG? Are people having good luck/good case fill with RL33?

I've heard 570 thrown around as a viable option, but it may as well not exist as far as I'm concerned. I've never seen it available anywhere.

I’ve had decent luck with rl33 but temp stability is some what noticeable. Case fill is good on rl33. H50bmg has worked as well. I’ve tried 277 mtac’s, 300 otm’s, and 285 flatlines. 3130fps is where I’m running the 285 flatline with rl33 and no pressure but I’m getting some primer flow around the firing pin on my MC(fairly common on these guns). Tried some 8133 but it seems to build pressure pretty quick.

I’ve worked up pretty good loads for the mtac’s and 285 flatlines that group well at 500 yds and ES 15 or so but when I get them both out to 2010 or 2750 yds I seem to get a random shot here or there that goes high or low for no reason. That kinda has me scratching my head on what to do next on tweaking LD.....

Gun specs:
AXMC
30” Bartlein 8-7 gain twist
Tbac 338 ultra
 
I’ve had decent luck with rl33 but temp stability is some what noticeable. Case fill is good on rl33. H50bmg has worked as well. I’ve tried 277 mtac’s, 300 otm’s, and 285 flatlines. 3130fps is where I’m running the 285 flatline with rl33 and no pressure but I’m getting some primer flow around the firing pin on my MC(fairly common on these guns). Tried some 8133 but it seems to build pressure pretty quick.

I’ve worked up pretty good loads for the mtac’s and 285 flatlines that group well at 500 yds and ES 15 or so but when I get them both out to 2010 or 2750 yds I seem to get a random shot here or there that goes high or low for no reason. That kinda has me scratching my head on what to do next on tweaking LD.....

Gun specs:
AXMC
30” Bartlein 8-7 gain twist
Tbac 338 ultra
I'm running an AXMC in the 300nm and also with the 338tbac. I get the random high shot as well. I wonder if we have something in common causing this? Have you had issues with other calibers with your axmc?